Hex couplers are used to connect two pieces of threaded material. Hex and heavy hex couplers are threaded right hand. If a right hand-left hand coupler is needed, consider using a sleeve nut.

See our nut compatibility chart to determine the compatible hex coupler for a specific grade of bolt. Since hot-dip galvanizing typically adds 2.2 to 5 mils of thickness to the threaded portion of a fastener, galvanized couplers are tapped oversize to compensate for the corrosion resistant coating on the bolts.

Stock

Diameters: 1/2″ – 1″
Origin: Domestic and import
Finish: Black and hot-dip galvanized
Grades: A563 (grades A and DH)

Available

Diameters: 1/2″ – 6″
Origin: Domestic and import
Finish: Black and hot-dip galvanized
Grades: A563 (grades A, C, and DH), A194 grade 2H

Dimensions

Finished Hex Coupler Pattern

Click table to show drawingHex Coupling Nut
Nominal SizeFCH
Width Across FlatsWidth Across CornersLength/Thickness
BasicMaxMinMaxMinBasicMaxMin
1/2 11/16 0.688 0.663 0.794 0.756 1 3/4 1.760 1.690
5/8 13/16 0.813 0.782 0.939 0.891 2 1/8 2.135 2.067
3/4 1 1.000 0.963 1.155 1.097 2 1/4 2.260 2.190
7/8 1-1/4 1.250 1.212 1.443 1.382 2 1/2 2.510 2.440
1 1-3/8 1.375 1.325 1.588 1.511 2 3/4 2.760 2.690
1-1/8 1-1/2 1.500 1.450 1.732 1.653 3 3.010 2.940
1-1/4 1-5/8 1.625 1.575 1.876 1.825 3 3.010 2.940
1-1/2 2 2.000 1.950 2.309 2.275 3 1/2 3.510 3.440
Dimensions per ASME B18.2.2 2010

Heavy Hex Coupler Pattern

Click table to show drawingHex Coupling Nut
Nominal Size F C H
Width Across Flats Width Across Corners Thickness
Basic Max Min Max Min Basic Max Min
1-5/8 2-9/16 2.562 2.481 2.959 2.828 4-7/8 4.91 4.83
1-3/4 2-3/4 2.750 2.662 3.175 3.035 5-1/4 5.29 5.21
1-7/8 2-15/16 2.938 2.844 3.392 3.242 5-5/8 5.67 5.58
2 3-1/8 3.125 3.025 3.608 3.449 6 6.04 5.95
2-1/4 3-1/2 3.500 3.388 4.041 3.862 6-3/4 6.80 6.70
2-1/2 3-7/8 3.875 3.750 4.474 4.275 7-1/2 7.55 7.44
2-3/4 4-1/4 4.250 4.112 4.907 4.688 8-1/4 8.31 8.19
3 4-5/8 4.625 4.475 5.340 5.102 9 9.06 8.94
3-1/4 5 5.000 4.838 5.774 5.515 9-3/4 9.81 9.68
3-1/2 5-3/8 5.375 5.200 6.207 5.928 10-1/2 10.57 10.43
3-3/4 5-3/4 5.750 5.562 6.640 6.341 11-1/4 11.32 11.17
4 6-1/8 6.125 5.925 7.073 6.755 12 12.08 11.92
4-1/2 6-7/8 6.875 6.650 7.939 7.581 13-1/2 - -
5 7-5/8 7.625 7.375 8.805 8.408 15 - -

Dimensions per ASME B18.2.2 1987 (R 1999) Note: Dimension may vary based on available raw material